Jaz Mini-HOWTO for NetBSD/mac68k
(for version 1.3)
by
Larry Kollar (kollar@stc.net)
Overview
This document provides guidelines for setting up a Jaz drive for use
with NetBSD/mac68k.
This document is geared toward users with a fair amount of MacOS
experience, and a limited amount of Un*x experience (Unix, NetBSD, Solaris,
Linux, NextStep, and many other similar systems are lumped together as
"Un*x"). Beyond the initial installation, this document contains only
a few references to other pages and books.
Instructions for setting up NetBSD can be found in the
NetBSD/mac68k Installation Guide[1].
About this document
This mini-HOWTO can be used on-line, or can be printed out.
Referenced documents are linked (where available) for on-line users; a
corresponding footnote lists the URL of these documents for use as a
printed document.
About the Jaz drive
NetBSD treats a Jaz drive like a standard SCSI disk. You can use it as
a boot drive (not recommended for constant usage due to heat-related
problems), or as a secondary mountable drive. Jaz drives can be partitioned
for both Mac and NetBSD use.
Acknowledgements
This document is based mainly on information from the port-mac68k
mailing list. However, any mistakes found here are my own. Please let me
know if you have any questions or improvements.
Disclaimer
Do I really need to insert all that legal mumbo-jumbo here?
If you wipe out five years' worth of software and data, and forgot to make
backups first....
Jaz driver software (MacOS)
You should have version 5.0 or newer of the Iomega driver. The latest
versions can be downloaded from Iomega's
web site[2]. Choose either one of the following versions:
Install the driver, then reboot the Mac. Open the Iomega Drive
Options control panel, select your Jaz drive, and set the options
as follows:
- Verify Disk Writes: uncheck this box while partitioning,
formatting, and installing software. Verify slows down disk writing
by a factor of roughly four. You may wish to turn it on after setting
up everything to see how it affects performance.
- Eject Disk at Shutdown: as desired
- Eject Disk on Restart: uncheck this box if you intend to boot
NetBSD from the Jaz drive (or be prepared to insert the cartridge
very quickly when it ejects!)
- Drive Sleep: leave at 30 minutes, or increase
the time if you wish (UNIX systems tend to access the disk a lot, so
the drive may spin down only rarely if ever)
Jaz drive requirements
To set up a Jaz drive for NetBSD, download the tools listed in the
Installation Guide[1]. You will also need
partitioning software as described in the same document. Then follow
the guidelines below.
Choosing a Kernel
- 68040-based Performa, Centris, or Quadra systems: use a kernel with
the generic (NCR) SCSI driver.
- Other systems: use a kernel with an SBC SCSI driver.
If you create a custom kernel, remember to configure in the proper
SCSI driver.
Sizing partitions
You can create as many partitions on the Jaz drive as your partitioning
software (and NetBSD) allow. The following scheme works well for a
boot drive; you can combine or resize partitions as desired.
- MacOS partition (70MB)
- NetBSD root partition (50MB)
- swap partition (35MB)
- /usr partition (200MB)
- /var partition (150MB)
- /home partition (515MB)
If you plan to use a Jaz cartridge for both MacOS and NetBSD, place
at least one MacOS partition first.
Using mkfs
Use mkfs to convert the A/UX partitions to NetBSD and to format
the partitions. When you format the drive, accept the default parameters
(mkfs displays zero cylinders in the list, but will do the right
thing).
Change the Optimization to Time; the Installer
will probably change it for you anyway.
Installing and booting
If you plan to boot NetBSD from the Jaz drive, set it up just like you
would a fixed hard drive. Booting is also identical.
[1] install.html
[2] ftp://ftp.iomega.com/pub/
Larry Kollar
Jan. 17, 1998